[win] Fallback to registry when finding external handlers for a protocol

[win] Fallback to registry when finding external handlers for a protocol

On windows 8 and later AssocQuery is used to find external protocol
handlers (e.g. to handle steam:// links). Prior versions use the
registry.

Some programs may not register in a way that AssocQuery recognizes, so
this change also consults the registry if AssocQuery does not return any
results.

BUG=560809
Committed: https://crrev.com/d0c67aafb743b03c57f12664b6ded94c2063b2f8
Cr-Commit-Position: refs/heads/master@{#408322}

[benwells, 2016-07-21 22:26:08]

benwells@chromium.org changed reviewers:
+ grt@chromium.org

[benwells, 2016-07-21 22:26:09]

Greg, does this make sense? See bug for more context.

[grt (UTC plus 2), 2016-07-22 10:37:59]

Makes sense to me. Windows does the right thing in this case, so Chrome should
too. LGTM. My only nit is that I would return the fallback value directly to
avoid the second assignment, but this is personal preference so feel free to do
whatever you like.

[benwells, 2016-07-28 01:25:28]

Tweaked slightly based on comment. Going to submit now, if it doesn't look good
to you please let me know and i'll adjust after.

[benwells, 2016-07-28 01:27:18]

The CQ bit was checked by benwells@chromium.org

[benwells, 2016-07-28 01:27:18]

The patchset sent to the CQ was uploaded after l-g-t-m from grt@chromium.org
Link to the patchset: https://codereview.chromium.org/2172573002/#ps60001
(title: "Tweaked")

[commit-bot: I haz the power, 2016-07-28 01:27:32]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-07-28 01:44:49]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-07-28 01:44:50]

Try jobs failed on following builders:
  android_arm64_dbg_recipe on master.tryserver.chromium.android (JOB_FAILED,
https://build.chromium.org/p/tryserver.chromium.android/builders/android_arm6...)

[benwells, 2016-07-28 02:40:07]

The CQ bit was checked by benwells@chromium.org

[commit-bot: I haz the power, 2016-07-28 02:40:24]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-07-28 02:57:35]

Committed patchset #4 (id:60001)

[commit-bot: I haz the power, 2016-07-28 02:58:45]

Description was changed from

==========
[win] Fallback to registry when finding external handlers for a protocol

On windows 8 and later AssocQuery is used to find external protocol
handlers (e.g. to handle steam:// links). Prior versions use the
registry.

Some programs may not register in a way that AssocQuery recognizes, so
this change also consults the registry if AssocQuery does not return any
results.

BUG=560809
==========

to

==========
[win] Fallback to registry when finding external handlers for a protocol

On windows 8 and later AssocQuery is used to find external protocol
handlers (e.g. to handle steam:// links). Prior versions use the
registry.

Some programs may not register in a way that AssocQuery recognizes, so
this change also consults the registry if AssocQuery does not return any
results.

BUG=560809

Committed: https://crrev.com/d0c67aafb743b03c57f12664b6ded94c2063b2f8
Cr-Commit-Position: refs/heads/master@{#408322}
==========

[commit-bot: I haz the power, 2016-07-28 02:58:46]

Patchset 4 (id:??) landed as
https://crrev.com/d0c67aafb743b03c57f12664b6ded94c2063b2f8
Cr-Commit-Position: refs/heads/master@{#408322}

[grt (UTC plus 2), 2016-07-28 06:30:20]

lgtm